|The PHASE SHIFTER changes the phase of the input signal and outputs it. There are various types according to the phase control system.
|Octave band method
This type is the lowest cost and most used. It is composed of 90deg hybrid and variable-capacitance diodes. The phase of the output signal can be continuously changed by the DC voltage control. The bandwidth is decided by the 90deg hybrid.
|Frequency conversion method
The input RF signal is converted into an intermediate frequency, and then, it is converted back into its former frequency. The phase of the output signal is changed by changing the phase of the local oscillation frequency signal used at this time. Even if the input frequency changes into this type, the amount of the phase change remains constant.
|PLL method (APC)
The output signal or external signal is compared in the phase with the input signal, and the phase of the output signal is changed depending on the amount of the delay in the feedback control loop. This type has the highest stability. It is possible to manufacture a phase shifter with a stability of less than ±0.1 degrees when used together with a homothermal box.
This type creates wideband with an IQ modulator, and the linearity is excellent.
|■FREQUENCY MULTIPLIER / DIVIDER
The frequency multiplier and the frequency divider are designed and manufactured.
In the range that can produce it, frequency is less than 6GHz.
The Frequency Multiplier generates an output signal with frequency equal to the integral multiple of its input signal frequency.
Our multiple ranges from two to several hundred. however, certain frequencies or multiples may not be manufactured.
The Frequency Divider generates an output signal whose frequency is divided by n (n:integer). However, certain frequencies or division ratios may not be manufactured.
|■PHASE MONITORING SYSTEM (PHASE COMPARATOR)
This is a monitoring apparatus where it measures the phase and amplitude of the two identical frequency signal with high accuracy. The measurement results displayed on the front panel and then output to the higher-level control system.
Down converts the monitor signal to an intermediate frequency of 12MHz, and then by acquiring at 48MHz, has obtain the phase information as the I,Q component. It is also possible to monitor simultaneously the amplitude information.
The VSWR Meter detects Pf(Forward) and Pr(Refrect) monitor signals inputted from up to four directional couplers, and then A/D-converts, corrects and calculates them so that the meter shows Forward power, Reflect power and VSWR on the monitor.
The offset values of the coupling factor of the directional couplers, the loss of the coaxial cable can be set as needed. As thresholds of the each display values can be set, the Meter can generate an alarm signal when an anomaly occures.